Capital, which claims to reach more than half the UK population, has made no secret of its ambition to expand through acquisitions.

Its radio stations include Capital FM, Manchester's Century 105.4FM, Capital Gold and Xfm, as well as regional stations such as Red Dragon in South Wales and BRMB in the Midlands.

GWR boasts more licences and a larger audience share than any other commercial radio group in the UK, with stations including Classic FM, as well as 33 local offerings such as Essex FM, Leicester Sound and Trent FM.